I think you are highlighting an issue here — the definition of sexual assault, that we need to explore more in public.
Our culture(s) usually have the male as the initiator or sex, and the woman as the more passive person in the “enterprise”.
While it has changed a bit over the decades, these roles still exist, in whole or in part.
And that makes the whole thing confusing and unclear.
There are obviously many situations that are clearly abusive, involving force, coercion, the use of power, threats, and so on that most of us would agree on.
Then there are the gray areas where male-female roles create situations of ambiguity, as you point out.
Without the roles changing to become more identical (and I’m not sure that will ever happen, clear rules to follow for both men and women are going to be hard to establish.
On one hand we don’t want to make sex and romance into something that has to be contracted in writing, but neither do we want to have the “male as sexual aggressor” run rampant.
PS. I’m glad I’m old and married!